Dihydropteridione intermediate compounds

A compound of the formula (A5)

• R1 and R2, which may be identical or different, denote hydrogen, or a group selected from among C1-C6-alkyl, C2-C6-alkenyl and C2-C6-alkynyl, which may optionally be mono- or polysubstituted by one or more groups R9, or
• R1 and R2 together denote C2-C6-alkylene, in which optionally one or two methylene groups may be replaced by one of the groups —O or —NR7, and which may optionally be mono- or polysubstituted by one or more groups R9;
• R3 denotes hydrogen or a group selected from C1-C8-alkyl, C2-C8-alkenyl, C2-C8-alkynyl, C3-C8-cycloalkyl and C6-C14-aryl, which may optionally be mono- or polysubstituted by one or more groups R9;
• or
• R7 denotes hydrogen or C1-C6-alkyl,
• R9 denotes halogen, C1-C4-alkyl, C1-C4-alkyloxy, CN, OH or CF3;
• optionally in the form of the tautomers, racemates, enantiomers, diastereomers and mixtures thereof, and optionally in the form of the acid addition salts thereof.